Light trough the object on render
There are numerous possibilities as to what causes this. I tried to list them in order of likelihood


your material for the lamp's glass material does not look transparent (you can set it to translucent, but be ready for some serious noise)
your lamp is too weak for cycles
your lamp's cycles visibility options don't make it show up where it's supposed to illuminate.


There's more, but please make sure the ones above don't apply and if not send another screenshot with the lamp selected, meaning showing its settings as well as its place in the outliner.